(scalar @x) is the length of @x here 3

(scalar @x) - 1 == 2

In other words

$x[-y] is a shortcut for $x[(scalar @x) - y]

=>

$x[-1] eq $x[2] eq "light"

$x[-2] eq $x[1] eq "bar"

$x[-3] eq $x[0] eq "foo"

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^3: What array negative number counting means by LanX
in thread What array negative number counting means by Anonymous Monk

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